Abstract
Introduction
Total knee arthroplasty [TKA] is a common procedure to relieve painful disability from advanced knee arthritis. However, related blood loss, ranging from 800 to 1200 ml, increase risk and disruption of recovery in anemic patients following TKA. Various methods for blood conservation had been proposed and examined. In the literature, the intra-articular administration of a solution mixing bupivacaine and epinephrine was commonly used after knee surgeries. Therefore, we conducted a retrospective, case controlled review of our primary TKAs to determine the hemostatic efficacy of this regimen following TKAs.
Material and Methods
Over a period of 12 months, 135 eligible patients were divided two groups simply according to the intra-articular injection or not: a control group (N=63) and a treatment group (N=72). In the treatment group, a 40 ml vial of 0.5% bupivacaine with epinephrine 1: 200000 was given prior to the deflation of pneumatic tourniquet. No drainage was used in all TKAs. Without recordable drainage, a Gross formula, considering gender and body composition, was used for estimate blood loss following TKAs. In addition, serial changes in hemoglobin as well as the requirement of allogenic transfusion were also compared between groups.
Results
The mean calculated blood loss in the treatment group was 650.4 +/− 257.1 ml, compared to 648.8+/− 222.1 ml in the control group (p=0.9). Similar decrease in hemoglobin as well as rates of allogenic transfusion needs were observed between groups.[2.5+/− 0.9 g/dl vs. 2.4+/− 0.8 g/dl; 13.9% vs. 12.7%, respectively]
Discussion and Conclusion
Although local analgesics mixing vasoconstrictive agents seem a logic solution to save blood loss and relieve pain simultaneously, the hypothesis that intra-articular injection of bupivacaine and epinephrine would save blood and even transfusion needs following TKAs is not supported by various bleeding parameters in this study. In addition to temporary benefit in pain relief, this regimen only has little effect on blood conservation. Therefore, new regimen as well as hemostatic means are still required and explored to reduce blood loss following TKAs.
